Nitraza amine compounds



United States Patent 3,000,954 NITRAZA AMINE COMPOUNDS Milton B. Frankel, Pasadena, Calif., assignor to Aeroietgfiueral Corporation, Azusa, Calif., a corporation of No Drawing. Filed June 13, 1957, Ser. No. 666,273 13 Claims. (Cl. 260-583) This invention relates to new nitraza compounds and to a method for preparing them. In particular this in vention relates to nitraza amines and their corresponding salts having the general formula:

wherein R is a hydrogen, alkyl or nitroalkyl radical and A is an alkylene radical.

The nitraza amines of the present invention condense with fl-geminal polynitro alcohols such as 2,2,2-trinitroethanol to form nitramine compounds (as more fully disclosed in assignees copending United States patent application Serial No. 666,276, filed concurrently with the present application) which react with nitric acid to form high energy nitramines, as more fully disclosed in assignees copending United States patent application Serial No. 666,274, filed concurrently with the present application.

In efiecting the condensation of the nitraza amines of this invention with the above-mentioned polynltroalcohols, it is preferred to generate them in situ from their corresponding salts of strong mineral acids by neutralization of said salts as more fully disclosed hereinbelow.

The high energy nitramines which are the end products of the above-described reactions are useful as high explosives and can be used in any conventional explosive missile, projectile, rocket, or the like, as the main explosive charge. An example of such a missile is disclosed in United States Patent 2,470,162, issued May 17, 1949. One way of using the high expl sives which can be prepared from the nitraza amine salts of the present invention in a device such as that disclosed in United States Patent No. 2,470,162 is to pack the crystalline explosive in powder form into the warhead of the missile. Alternatively, the crystals can be first pelletized and then packed. A charge thus prepared is sufficiently insensitive to withstand the shock entailed in the ejection of a shell from a gun barrel or from a rocket launching tube under the pressure developed from ignition of a propellant charge, and can be caused to explode on operation of an impact-or time-fuse mechanism firing a detonating explosive such as lead azide or mercury fulminate.

The novel ntra amine salts f this invention are pren r d b re tin "tram 's c avs with aoueous solutions of strong mineral acids in accordance with the general reaction scheme set forth below:

wherein R and A are as previously defined and X is a monovalent anion of a strong mineral acid.

The corresponding free nitraza amines can be generated from the nitraza amine salts of the present invention by neutralizing the salts with inorganic basic salts of alkali or alkaline earth metals, such as hydroxides or carbonates, or weak organic acid salts such as acetates, of alkali or alkaline earth metals. For reasons of convenience and economy it is preferred to use sodium hydroxide as the amine generating agent, but other suitable "ice generating agents such as calcium hydroxide, magnesium hydroxide, sodium carbonate, sodium acetate, calcium acetate, etc. can be used for this purpose.

To more clearly illustrate my invention, the following examples are presented. It should be understood that these examples are presented merely as a means of illustration and are not intended to limit the scope of the invention in any way.

EXAMPLE I Preparation of 3-nilraza-1butyl ammonium nitrate To twenty-nine grams (-0.2 mole) of 3-nitraza-l-butyl isocyanate was added fifty milliliters of aqueous acid solution of 35 percent HN-O concentration, upon which a vigorous reaction, with evolution of carbon dioxide gas, took place. The reactive solution was heated on a steam-bath for one hour to bring about substantial completion of the reaction. After the steam-bath treatment, the solution was concentrated in vacuo to give a quantitative yield of a white solid. The white solid was recrystallized from methanol as white needle-shaped crystals having a melting point of l20-12l C. The needleshaped crystals were the final product, 3-nitraza-1-butyl ammonia nitrate. The elemental analysis of the product appears below:

Caculated for C H N O :percent C., 19.78; percent H, 5.53. Found: percent C, 20.02; percent H, 5.26.

EXAMPLE II Preparation of 3-nitraza-1-butyl ammonium chloride Following the procedure of Example I using hydrochloric acid in place of nitric acid, yielded S-nitrazal-butyl ammonium chloride. The melting point of the final product was found to be 132"l33 C.

Reaction temperature is non-critical in the practice of my invention, the only eflect of temperature variation being a corresponding increase or decrease in reaction rate. Thus, the mixtures of nitraza isocyanates and strong mineral acids can be maintained at an elevated temperature if desired to increase the rate of reaction.

The nitraza isocyanates, useful as starting materials in the practice of this invention, are obtained by reacting nitraza-acid halides, such as 4-nitraza-pentanoyl chloride, with alkali or alkaline earth metal azides, such as sodium azide or magnesium azide, to form the corresponding nitraza azides, and then heating said nitraza azides to effect rearrangement to the desired nitraza isocyanate form. Treating the above-mentioned 4-nitrazapentanoyl chloride as described results in the formation of 3-nitraza-l-butyl isocyanate. This method of preparing nitraza isocyanates is more fully disclosed in my copending United States patent application Serial 4 384. filed June 9, 1955.

The strong mineral acid with which the nitraza isocyanate is reacted in the present invention can be any strong mineral acid such as hydrochloric acid, nitric acid, suluric acid. phosphoric acid or the like.

It will be appreciated that a wide variety of nitraza amine compounds can be prepared in accordance with the teachings of this invention. For example, 4-nitrazal-hexyl isocyanate and 3-aza-3,5,5-trinitro-l-hexyl isocyanate react with strong mineral acids to produce the corresponding strong mineral acid salts of 4-nitraza-lhexylamine and 3-aza-3,5,5-trinitro-l-hexylamine, respectively. The free nitraza amines can be readily generated from these acid salts through neutralization thereof with an inorganic basic salt or a weak organic acid salt of an alkali or an alkaline earth metal s taught herein.

I claim:

1. As a composition of matter, a nitraza compound selected from the group consisting of nitraza amines having the formula:

n-om-zs-a-cm-rm: wherein R is a radical selected from the group consisting of hydrogen, lower alkyl and lower nitroalkyl radicals, and A is a lower alkylene radical, and strong mineral acid salts thereof.

2. As a composition of matter, a nitraza amine having the formula:

R-NACH:NH: wherein R is a lower alkyl radical and A is a lower alkylene radical.

3. As a composition of matter, a nitraza amine having the formula:

1110: RCH:N--A-CH2NH9 wherein R is a lower nitroalkyl radical and A is a lower alkylene radical.

4. As a composition of matter, a nitraza amine salt having the formula:

1 :0, RN-A--CH:NH;.HX wherein R is a lower alkyl radical, A is a lower alkylene radical, and X is a monovalent anionic radical from a strong mineral acid.

5. As a composition of matter, a nitraza amine salt having the formula:

IIIO: R-CHrN-AOHrNHz-HX wherein R is a lower nitroalkyl radical, A is a lower alkylene radical, and X is a monovalent anionic radical from a strong mineral acid.

6. As a composition of matter, 3-nitrazabutyl ammonium nitrate having the structural formula:

7. As a composition of matter, 3-nitrazabutyl ammo nium chloride having the structural formula:

8. The method of preparing strong mineral acid salts of a nitraza compound selected from the group consisting of nitraza amines having the formula:

IIIO: RCHrNA-CHz-NH: comprising reacting a nitraza isocyanate of the formula:

I: ROHr-NA-C Hr-NC o with an aqueous solution of a strong mineral acid; wherein R is a radical selected from the group consisting of hydrogen, lower alkyl, and lower nitroalkyl radicals, and A is a lower alkylene radical.

9. The method of preparing a nitraza amine salt having the formula:

RCH -NACH -NH=-HX which comprises reacting a nitraza isocyanate with an aqueous solution of a strong mineral acid; wherein R is a radical selected from the group consisting of hydrogen, lower alkyl, and lower nitroalkyl radicals; A is a lower alkylene radical; and X is the monovalent anionic radical from the strong mineral acid.

10. The method of claim 9, in which the nitraza isocyanate has the formula:

wherein R is a lower alkyl radical and A is a lower alkylene radical.

11. The method of claim 9, in which the nitraza isocyanate has the formula:

wherein R is a lower nitroalkyl radical and A is a lower alkylene radical.

12. The method of preparing S-nitraza-l-butyl ammonium nitrate which comprises reacting 3-nitraza-1- butyl isocyanate with an aqueous solution of nitric acid.

13. The method of preparing B-nitraza-l-butyl ammonium chloride which comprises reacting 3-nitraza-1-butyl isocyanate with an aqueous solution of hydrochloric acid.

No references cited. 

1. AS A COMPOSITION OF MATTER, A NITRAZA COMPOUND SELECTED FROM THE GROUP CONSISTING OF NITRAZA AMINES HAVING THE FORMULA: 